Prevention of contrast-induced nephropathy with volume expansion

Background and objectives: Contrast-induced nephropathy is one of the few preventable forms of acute kidney injury. Several pharmacologic agents have been evaluated for the prevention of contrast-induced nephropathy, yet disappointingly, few have been shown conclusively to reduce the risk for this condition. A series of studies have demonstrated that volume expansion, particularly with intravenous fluids, is an effective intervention to reduce the risk for contrast-induced nephropathy. Design, setting, participants, & measurements: This article reviews the clinical trials that have assessed the role of volume expansion for the prevention of contrast-induced nephropathy. Results: The administration of isotonic sodium chloride before and after radiocontrast injection seems to be more protective than equivalent volumes of hypotonic saline and, when feasible, should be administered over a sustained period of time. Recent clinical trials suggested that an abbreviated regimen of intravenous sodium bicarbonate may be superior to a comparable protocol of sodium chloride. Although a small number of studies have found that volume supplementation by mouth may be effective in preventing contrast-induced nephropathy, the routine use of enteral fluids or solute in lieu of intravenous fluids in high-risk patients cannot be recommended at this time. Rather, liberal oral fluid and solute intake should complement intravenous fluid administration to minimize risk. Conclusions: Future studies will be required to define clearly the optimal prophylactic intravenous fluid regimen for contrast-induced nephropathy and further delineate the independent role of oral volume expansion for the prevention of this condition.